Efficient Paging and Idle Mode Wakeup for Wireless Devices Supporting Coverage Enhanced Mode

ABSTRACT

This disclosure relates to techniques for efficient idle mode wakeup for wireless devices supporting an enhanced coverage mode and a normal coverage mode in a wireless communication system. A wireless device may camp on a cellular base station in idle mode. The wireless device may monitor a control channel associated with the normal coverage mode during a paging occasion. The wireless device may also monitor a control channel associated with the enhanced coverage mode during the paging occasion if a paging indication is not successfully decoded on the control channel associated with the normal coverage mode.

PRIORITY INFORMATION

This application is a divisional of U.S. application Ser. No.16/511,242, entitled “Efficient Paging and Idle Mode Wakeup for WirelessDevices Supporting Coverage Enhanced Mode”, and filed Jul. 15, 2019,which is a continuation of U.S. application Ser. No. 15/888,929,entitled “Efficient Paging and Idle Mode Wakeup for Wireless DevicesSupporting Coverage Enhanced Mode” and filed Feb. 5, 2018, which claimspriority to U.S. provisional patent application Ser. No. 62/456,947,entitled “Efficient Paging and Idle Mode Wakeup for Wireless DevicesSupporting Coverage Enhanced Mode,” filed Feb. 9, 2017, and to U.S.provisional patent application Ser. No. 62/471,507, entitled “EfficientPaging and Idle Mode Wakeup for Wireless Devices Supporting CoverageEnhanced Mode,” filed Mar. 15, 2017, each of which are herebyincorporated by reference in their entirety as though fully andcompletely set forth herein.

The claims in the instant application are different than those of theparent application or other related applications. The Applicanttherefore rescinds any disclaimer of claim scope made in the parentapplication or any predecessor application in relation to the instantapplication. The Examiner is therefore advised that any such previousdisclaimer and the cited references that it was made to avoid, may needto be revisited. Further, any disclaimer made in the instant applicationshould not be read into or against the parent application or otherrelated applications.

TECHNICAL FIELD

The present application relates to wireless communication, including totechniques for efficient paging and idle mode wakeup for wirelessdevices supporting coverage enhanced mode in a wireless communicationsystem.

DESCRIPTION OF THE RELATED ART

Wireless communication systems are rapidly growing in usage. Further,wireless communication technology has evolved from voice-onlycommunications to also include the transmission of data, such asInternet and multimedia content.

Mobile electronic devices may take the form of smart phones or tabletsthat a user typically carries. Wearable devices (also referred to asaccessory devices) are a newer form of mobile electronic device, oneexample being smart watches. Additionally, low-cost low-complexitywireless devices intended for stationary or nomadic deployment are alsoproliferating as part of the developing “Internet of Things”. Many suchdevices have relatively limited wireless communications capabilities andtypically have smaller batteries than larger portable devices, such assmart phones and tablets. In general, it would be desirable to recognizeand provide support for the relatively limited wireless communicationcapabilities of such devices. Therefore, improvements in the field aredesired.

SUMMARY

Embodiments are presented herein of, inter alia, systems, apparatuses,and methods for efficient paging and idle mode wakeup for wirelessdevices supporting coverage enhanced mode in a wireless communicationsystem.

According to some of the embodiments described herein, a cellular basestation may select a paging arrangement to use from among multiplepossible paging arrangements. The paging arrangement used may depend atleast in part on cell loading or other considerations that may bespecific to the cellular base station. For example, if not particularlyloaded, it may be possible for the cellular base station to use anarrangement whereby a control channel associated with enhanced coverageconditions may always be used for paging. With such an arrangement,devices served by the base station may have a relatively likelihood ofbeing able to detect and decode paging indications. Alternatively, ifthe base station is relatively loaded (e.g., such that always using thecontrol channel associated with enhanced coverage conditions for pagingmay be difficult), an alternative arrangement may be used.

The alternative arrangement may include attempting to page on onecontrol channel initially, and subsequently attempting to page onanother control channel, e.g., if attempts to page on the initialcontrol channel are unsuccessful. The order in which the controlchannels are used for paging attempts may be selected based on whichcontrol channel is considered most likely to be monitored by thewireless device being paged, on which control channel the wirelessdevice being paged is considered most likely to be able to successfullydetect and decode a paging indication, and/or based on any of variousother possible considerations.

At least in some instances, a wireless device may adapt how it performspage monitoring based on the cellular base station's selected pagingarrangement. For example, if an arrangement in which a control channelassociated with enhanced coverage conditions is always used for paging,the wireless device may always monitor that control channel. If analternative arrangement in which the base station may initially attemptto page on one control channel and may subsequently attempt to page onanother control channel if unsuccessful on the initial control channel,the wireless device may monitor both control channels that maypotentially be used.

Additionally or alternatively, the wireless device may select a controlchannel to monitor for paging indications based on its current coverageconditions. For example, if the base station will initially attempt topage on one control channel and subsequently attempt to page on anothercontrol channel if unsuccessful on the initial control channel, and thewireless device is in poor coverage conditions such that the wirelessdevice can determine that it would be unlikely to be capable ofdetecting and/or decoding a paging indication on a control channelassociated with normal coverage conditions, the wireless device mayforego monitoring that control channel and only monitor a controlchannel associated with enhanced coverage conditions.

The techniques described herein may be implemented in and/or used with anumber of different types of devices, including but not limited tocellular phones, tablet computers, accessory and/or wearable computingdevices, portable media players, cellular base stations and othercellular network infrastructure equipment, servers, and any of variousother computing devices.

This summary is intended to provide a brief overview of some of thesubject matter described in this document. Accordingly, it will beappreciated that the above-described features are merely examples andshould not be construed to narrow the scope or spirit of the subjectmatter described herein in any way. Other features, aspects, andadvantages of the subject matter described herein will become apparentfrom the following Detailed Description, Figures, and Claims.

BRIEF DESCRIPTION OF THE DRAWINGS

A better understanding of the present subject matter can be obtainedwhen the following detailed description of the embodiments is consideredin conjunction with the following drawings.

FIG. 1 illustrates an example wireless communication system including anaccessory device, according to some embodiments;

FIG. 2 illustrates an example system where an accessory device canselectively either directly communicate with a cellular base station orutilize the cellular capabilities of an intermediate or proxy devicesuch as a smart phone, according to some embodiments;

FIG. 3 is a block diagram illustrating an example wireless device,according to some embodiments;

FIG. 4 is a block diagram illustrating an example base station,according to some embodiments;

FIG. 5 illustrates examples of possible normal and extended coveragecell ranges, according to some embodiments;

FIGS. 6-7 are communication flow diagrams illustrating example methodsfor efficient paging for a wireless device supporting coverage enhancedmode, according to some embodiments; and

FIG. 8 is a timing diagram illustrating various possible idle modewakeup timing scenarios for decoding paging messages provided on themPDCCH, according to some embodiments.

While the features described herein are susceptible to variousmodifications and alternative forms, specific embodiments thereof areshown by way of example in the drawings and are herein described indetail. It should be understood, however, that the drawings and detaileddescription thereto are not intended to be limiting to the particularform disclosed, but on the contrary, the intention is to cover allmodifications, equivalents and alternatives falling within the spiritand scope of the subject matter as defined by the appended claims.

DETAILED DESCRIPTION Terminology

The following are definitions of terms used in this disclosure:

Memory Medium—Any of various types of non-transitory memory devices orstorage devices. The term “memory medium” is intended to include aninstallation medium, e.g., a CD-ROM, floppy disks, or tape device; acomputer system memory or random access memory such as DRAM, DDR RAM,SRAM, EDO RAM, Rambus RAM, etc.; a non-volatile memory such as a Flash,magnetic media, e.g., a hard drive, or optical storage; registers, orother similar types of memory elements, etc. The memory medium mayinclude other types of non-transitory memory as well or combinationsthereof. In addition, the memory medium may be located in a firstcomputer system in which the programs are executed, or may be located ina second different computer system which connects to the first computersystem over a network, such as the Internet. In the latter instance, thesecond computer system may provide program instructions to the firstcomputer for execution. The term “memory medium” may include two or morememory mediums which may reside in different locations, e.g., indifferent computer systems that are connected over a network. The memorymedium may store program instructions (e.g., embodied as computerprograms) that may be executed by one or more processors.

Carrier Medium—a memory medium as described above, as well as a physicaltransmission medium, such as a bus, network, and/or other physicaltransmission medium that conveys signals such as electrical,electromagnetic, or digital signals.

Programmable Hardware Element—includes various hardware devicescomprising multiple programmable function blocks connected via aprogrammable interconnect. Examples include FPGAs (Field ProgrammableGate Arrays), PLDs (Programmable Logic Devices), FPOAs (FieldProgrammable Object Arrays), and CPLDs (Complex PLDs). The programmablefunction blocks may range from fine grained (combinatorial logic or lookup tables) to coarse grained (arithmetic logic units or processorcores). A programmable hardware element may also be referred to as“reconfigurable logic”.

Computer System—any of various types of computing or processing systems,including a personal computer system (PC), mainframe computer system,workstation, network appliance, Internet appliance, personal digitalassistant (PDA), television system, grid computing system, or otherdevice or combinations of devices. In general, the term “computersystem” can be broadly defined to encompass any device (or combinationof devices) having at least one processor that executes instructionsfrom a memory medium.

User Equipment (UE) (or “UE Device”)—any of various types of computersystems or devices which are mobile or portable and which performwireless communications. Examples of UE devices include mobiletelephones or smart phones (e.g., iPhone™, Android™-based phones),portable gaming devices (e.g., Nintendo DS™, PlayStation Portable™,Gameboy Advance™, iPhone™), laptops, wearable devices (e.g. smart watch,smart glasses), PDAs, portable Internet devices, music players, datastorage devices, or other handheld devices, etc. In general, the term“UE” or “UE device” can be broadly defined to encompass any electronic,computing, and/or telecommunications device (or combination of devices)which is easily transported by a user and capable of wirelesscommunication.

Wireless Device—any of various types of computer systems or deviceswhich perform wireless communications. A wireless device can be portable(or mobile) or may be stationary or fixed at a certain location. A UE isan example of a wireless device.

Communication Device—any of various types of computer systems or devicesthat perform communications, where the communications can be wired orwireless. A communication device can be portable (or mobile) or may bestationary or fixed at a certain location. A wireless device is anexample of a communication device. A UE is another example of acommunication device.

Base Station—The term “Base Station” (also called “eNB”) has the fullbreadth of its ordinary meaning, and at least includes a wirelesscommunication station installed at a fixed location and used tocommunicate as part of a wireless cellular communication system.

Link Budget Limited—includes the full breadth of its ordinary meaning,and at least includes a characteristic of a wireless device (e.g., a UE)which exhibits limited communication capabilities, or limited power,relative to a device that is not link budget limited, or relative todevices for which a radio access technology (RAT) standard has beendeveloped. A wireless device that is link budget limited may experiencerelatively limited reception and/or transmission capabilities, which maybe due to one or more factors such as device design, device size,battery size, antenna size or design, transmit power, receive power,current transmission medium conditions, and/or other factors. Suchdevices may be referred to herein as “link budget limited” (or “linkbudget constrained”) devices. A device may be inherently link budgetlimited due to its size, battery power, and/or transmit/receive power.For example, a smart watch that is communicating over LTE or LTE-A witha base station may be inherently link budget limited due to its reducedtransmit/receive power and/or reduced antenna. Wearable devices, such assmart watches, are generally link budget limited devices. Alternatively,a device may not be inherently link budget limited, e.g., may havesufficient size, battery power, and/or transmit/receive power for normalcommunications over LTE or LTE-A, but may be temporarily link budgetlimited due to current communication conditions, e.g., a smart phonebeing at the edge of a cell, etc. It is noted that the term “link budgetlimited” includes or encompasses power limitations, and thus a powerlimited device may be considered a link budget limited device.

Processing Element (or Processor)—refers to various elements orcombinations of elements. Processing elements include, for example,circuits such as an ASIC (Application Specific Integrated Circuit),portions or circuits of individual processor cores, entire processorcores, individual processors, programmable hardware devices such as afield programmable gate array (FPGA), and/or larger portions of systemsthat include multiple processors.

Automatically—refers to an action or operation performed by a computersystem (e.g., software executed by the computer system) or device (e.g.,circuitry, programmable hardware elements, ASICs, etc.), without userinput directly specifying or performing the action or operation. Thusthe term “automatically” is in contrast to an operation being manuallyperformed or specified by the user, where the user provides input todirectly perform the operation. An automatic procedure may be initiatedby input provided by the user, but the subsequent actions that areperformed “automatically” are not specified by the user, i.e., are notperformed “manually”, where the user specifies each action to perform.For example, a user filling out an electronic form by selecting eachfield and providing input specifying information (e.g., by typinginformation, selecting check boxes, radio selections, etc.) is fillingout the form manually, even though the computer system must update theform in response to the user actions. The form may be automaticallyfilled out by the computer system where the computer system (e.g.,software executing on the computer system) analyzes the fields of theform and fills in the form without any user input specifying the answersto the fields. As indicated above, the user may invoke the automaticfilling of the form, but is not involved in the actual filling of theform (e.g., the user is not manually specifying answers to fields butrather they are being automatically completed). The presentspecification provides various examples of operations beingautomatically performed in response to actions the user has taken.

Configured to—Various components may be described as “configured to”perform a task or tasks. In such contexts, “configured to” is a broadrecitation generally meaning “having structure that” performs the taskor tasks during operation. As such, the component can be configured toperform the task even when the component is not currently performingthat task (e.g., a set of electrical conductors may be configured toelectrically connect a module to another module, even when the twomodules are not connected). In some contexts, “configured to” may be abroad recitation of structure generally meaning “having circuitry that”performs the task or tasks during operation. As such, the component canbe configured to perform the task even when the component is notcurrently on. In general, the circuitry that forms the structurecorresponding to “configured to” may include hardware circuits.

Various components may be described as performing a task or tasks, forconvenience in the description. Such descriptions should be interpretedas including the phrase “configured to.” Reciting a component that isconfigured to perform one or more tasks is expressly intended not toinvoke 35 U.S.C. § 112, paragraph six, interpretation for thatcomponent.

FIGS. 1-2—Wireless Communication System

FIG. 1 illustrates an example of a wireless cellular communicationsystem. It is noted that FIG. 1 represents one possibility among many,and that features of the present disclosure may be implemented in any ofvarious systems, as desired. For example, embodiments described hereinmay be implemented in any type of wireless device.

As shown, the exemplary wireless communication system includes acellular base station 102, which communicates over a transmission mediumwith one or more wireless devices 106A, 106B, etc., as well as accessorydevice 107. Wireless devices 106A, 106B, and 107 may be user devices,which may be referred to herein as “user equipment” (UE) or UE devices.

The base station 102 may be a base transceiver station (BTS) or cellsite, and may include hardware that enables wireless communication withthe UE devices 106A, 106B, and 107. The base station 102 may also beequipped to communicate with a network 100 (e.g., a core network of acellular service provider, a telecommunication network such as a publicswitched telephone network (PSTN), and/or the Internet, among variouspossibilities). Thus, the base station 102 may facilitate communicationamong the UE devices 106 and 107 and/or between the UE devices 106/107and the network 100. In other implementations, base station 102 can beconfigured to provide communications over one or more other wirelesstechnologies, such as an access point supporting one or more WLANprotocols, such as 802.11 a, b, g, n, ac, ad, and/or ax, or LTE in anunlicensed band (LAA).

The communication area (or coverage area) of the base station 102 may bereferred to as a “cell.” The base station 102 and the UEs 106/107 may beconfigured to communicate over the transmission medium using any ofvarious radio access technologies (RATs) or wireless communicationtechnologies, such as GSM, UMTS (WCDMA, TDS-CDMA), LTE, LTE-Advanced(LTE-A), 5G-NR, HSPA, 3GPP2 CDMA2000 (e.g., 1×RTT, 1×EV-DO, HRPD,eHRPD), Wi-Fi, WiMAX etc.

Base station 102 and other similar base stations (not shown) operatingaccording to one or more cellular communication technologies may thus beprovided as a network of cells, which may provide continuous or nearlycontinuous overlapping service to UE devices 106A-B and 107 and similardevices over a geographic area via one or more cellular communicationtechnologies.

Note that at least in some instances a UE device 106/107 may be capableof communicating using any of multiple wireless communicationtechnologies. For example, a UE device 106/107 might be configured tocommunicate using one or more of GSM, UMTS, CDMA2000, WiMAX, LTE, LTE-A,NR, WLAN, Bluetooth, one or more global navigational satellite systems(GNSS, e.g., GPS or GLONASS), one and/or more mobile televisionbroadcasting standards (e.g., ATSC-M/H), etc. Other combinations ofwireless communication technologies (including more than two wirelesscommunication technologies) are also possible. Likewise, in someinstances a UE device 106/107 may be configured to communicate usingonly a single wireless communication technology.

The UEs 106A and 106B are typically handheld devices such as smartphones or tablets, but may be any of various types of device withcellular communications capability. For example, one or more of the UEs106A and 106B may be a wireless device intended for stationary ornomadic deployment such as an appliance, measurement device, controldevice, etc. The UE 106B may be configured to communicate with the UEdevice 107, which may be referred to as an accessory device 107. Theaccessory device 107 may be any of various types of wireless devices,typically a wearable device that has a smaller form factor, and may havelimited battery, output power and/or communications abilities relativeto UEs 106. As one common example, the UE 106B may be a smart phonecarried by a user, and the accessory device 107 may be a smart watchworn by that same user. The UE 106B and the accessory device 107 maycommunicate using any of various short range communication protocols,such as Bluetooth or Wi-Fi.

The accessory device 107 includes cellular communication capability andhence is able to directly communicate with cellular base station 102.However, since the accessory device 107 is possibly one or more ofcommunication, output power and/or battery limited, the accessory device107 may in some instances selectively utilize the UE 106B as a proxy forcommunication purposes with the base station 102 and hence to thenetwork 100. In other words, the accessory device 107 may selectivelyuse the cellular communication capabilities of the UE 106B to conductits cellular communications. The limitation on communication abilitiesof the accessory device 107 can be permanent, e.g., due to limitationsin output power or the radio access technologies (RATs) supported, ortemporary, e.g., due to conditions such as current battery status,inability to access a network, or poor reception.

FIG. 2 illustrates an example accessory device 107 in communication withbase station 102. The accessory device 107 may be a wearable device suchas a smart watch. The accessory device 107 may comprise cellularcommunication capability and be capable of directly communicating withthe base station 102 as shown. When the accessory device 107 isconfigured to directly communicate with the base station, the accessorydevice may be said to be in “autonomous mode.”

The accessory device 107 may also be capable of communicating withanother device (e.g., UE 106), referred to as a proxy device orintermediate device, using a short range communications protocol; forexample, the accessory device 107 may according to some embodiments be“paired” with the UE 106. Under some circumstances, the accessory device107 may use the cellular functionality of this proxy device forcommunicating cellular voice/data with the base station 102. In otherwords, the accessory device 107 may provide voice/data packets intendedfor the base station 102 over the short range link to the UE 106, andthe UE 106 may use its cellular functionality to transmit (or relay)this voice/data to the base station on behalf of the accessory device107. Similarly, the voice/data packets transmitted by the base stationand intended for the accessory device 107 may be received by thecellular functionality of the UE 106 and then may be relayed over theshort range link to the accessory device. As noted above, the UE 106 maybe a mobile phone, a tablet, or any other type of hand-held device, amedia player, a computer, a laptop or virtually any type of wirelessdevice. When the accessory device 107 is configured to indirectlycommunicate with the base station using the cellular functionality of anintermediate or proxy device, the accessory device may be said to be in“relay mode.”

The UE 106 and/or 107 may include a device or integrated circuit forfacilitating cellular communication, referred to as a cellular modem.The cellular modem may include one or more processors (processingelements) and various hardware components as described herein. The UE106 and/or 107 may perform any of the method embodiments describedherein by executing instructions on one or more programmable processors.Alternatively, or in addition, the one or more processors may be one ormore programmable hardware elements such as an FPGA (field-programmablegate array), or other circuitry, that is configured to perform any ofthe method embodiments described herein, or any portion of any of themethod embodiments described herein. The cellular modem described hereinmay be used in a UE device as defined herein, a wireless device asdefined herein, or a communication device as defined herein. Thecellular modem described herein may also be used in a base station orother similar network side device.

The UE 106 and/or 107 may include one or more antennas for communicatingusing two or more wireless communication protocols or radio accesstechnologies. In some embodiments, the UE device 106/107 might beconfigured to communicate using a single shared radio. The shared radiomay couple to a single antenna, or may couple to multiple antennas(e.g., for MIMO) for performing wireless communications. Alternatively,the UE device 106/107 may include two or more radios. Otherconfigurations are also possible.

The accessory device 107 may be any of various types of devices that, insome embodiments, have a smaller form factor relative to a conventionalsmart phone, and may have one or more of limited communicationcapabilities, limited output power, or limited battery life relative toa conventional smart phone. As noted above, in some embodiments, theaccessory device 107 is a smart watch or other type of wearable device.As another example, the accessory device 107 may be a tablet device,such as an iPad, with Wi-Fi capabilities (and possibly limited or nocellular communication capabilities), which is not currently near aWi-Fi hotspot and hence is not currently able to communicate over Wi-Fiwith the Internet. Thus, as defined above, the term “accessory device”refers to any of various types of devices that in some instances havelimited or reduced communication capabilities and hence may selectivelyand opportunistically utilize the UE 106 as a proxy for communicationpurposes for one or more applications and/or RATs. When the UE 106 iscapable of being used by the accessory device 107 as a proxy, the UE 106may be referred to as a companion device to the accessory device 107.

FIG. 3—Block Diagram of a UE Device

FIG. 3 illustrates one possible block diagram of an UE device, such asUE device 106 or 107. As shown, the UE device 106/107 may include asystem on chip (SOC) 300, which may include portions for variouspurposes. For example, as shown, the SOC 300 may include processor(s)302 which may execute program instructions for the UE device 106/107,and display circuitry 304 which may perform graphics processing andprovide display signals to the display 360. The SOC 300 may also includemotion sensing circuitry 370 which may detect motion of the UE 106, forexample using a gyroscope, accelerometer, and/or any of various othermotion sensing components. The processor(s) 302 may also be coupled tomemory management unit (MMU) 340, which may be configured to receiveaddresses from the processor(s) 302 and translate those addresses tolocations in memory (e.g., memory 306, read only memory (ROM) 350, flashmemory 310). The MMU 340 may be configured to perform memory protectionand page table translation or set up. In some embodiments, the MMU 340may be included as a portion of the processor(s) 302.

As shown, the SOC 300 may be coupled to various other circuits of the UE106/107. For example, the UE 106/107 may include various types of memory(e.g., including NAND flash 310), a connector interface 320 (e.g., forcoupling to a computer system, dock, charging station, etc.), thedisplay 360, and wireless communication circuitry 330 (e.g., for LTE,LTE-A, NR, CDMA2000, Bluetooth, Wi-Fi, NFC, GPS, etc.).

The UE device 106/107 may include at least one antenna, and in someembodiments multiple antennas 335 a and 335 b, for performing wirelesscommunication with base stations and/or other devices. For example, theUE device 106/107 may use antennas 335 a and 335 b to perform thewireless communication. As noted above, the UE device 106/107 may insome embodiments be configured to communicate wirelessly using aplurality of wireless communication standards or radio accesstechnologies (RATs).

The wireless communication circuitry 330 may include Wi-Fi Logic 332, aCellular Modem 334, and Bluetooth Logic 336. The Wi-Fi Logic 332 is forenabling the UE device 106/107 to perform Wi-Fi communications on an802.11 network. The Bluetooth Logic 336 is for enabling the UE device106/107 to perform Bluetooth communications. The cellular modem 334 maybe a lower power cellular modem capable of performing cellularcommunication according to one or more cellular communicationtechnologies.

As described herein, UE 106/107 may include hardware and softwarecomponents for implementing embodiments of this disclosure. For example,one or more components of the wireless communication circuitry 330(e.g., cellular modem 334) of the UE device 106/107 may be configured toimplement part or all of the methods described herein, e.g., by aprocessor executing program instructions stored on a memory medium(e.g., a non-transitory computer-readable memory medium), a processorconfigured as an FPGA (Field Programmable Gate Array), and/or usingdedicated hardware components, which may include an ASIC (ApplicationSpecific Integrated Circuit).

FIG. 4—Block Diagram of a Base Station

FIG. 4 illustrates an example block diagram of a base station 102,according to some embodiments. It is noted that the base station of FIG.4 is merely one example of a possible base station. As shown, the basestation 102 may include processor(s) 404 which may execute programinstructions for the base station 102. The processor(s) 404 may also becoupled to memory management unit (MMU) 440, which may be configured toreceive addresses from the processor(s) 404 and translate thoseaddresses to locations in memory (e.g., memory 460 and read only memory(ROM) 450) or to other circuits or devices.

The base station 102 may include at least one network port 470. Thenetwork port 470 may be configured to couple to a telephone network andprovide a plurality of devices, such as UE devices 106/107, access tothe telephone network as described above in FIGS. 1 and 2.

The network port 470 (or an additional network port) may also oralternatively be configured to couple to a cellular network, e.g., acore network of a cellular service provider. The core network mayprovide mobility related services and/or other services to a pluralityof devices, such as UE devices 106/107. For example, the core networkmay include a mobility management entity (MME), e.g., for providingmobility management services, a serving gateway (SGW) and/or packet datanetwork gateway (PGW), e.g., for providing external data connectionssuch as to the Internet, etc. In some cases, the network port 470 maycouple to a telephone network via the core network, and/or the corenetwork may provide a telephone network (e.g., among other UE devicesserviced by the cellular service provider).

The base station 102 may include at least one antenna 434, and possiblymultiple antennas. The antenna(s) 434 may be configured to operate as awireless transceiver and may be further configured to communicate withUE devices 106/107 via radio 430. The antenna(s) 434 communicates withthe radio 430 via communication chain 432. Communication chain 432 maybe a receive chain, a transmit chain or both. The radio 430 may beconfigured to communicate via various wireless communication standards,including, but not limited to, LTE, LTE-A, NR, GSM, UMTS, CDMA2000,Wi-Fi, etc.

The base station 102 may be configured to communicate wirelessly usingmultiple wireless communication standards. In some instances, the basestation 102 may include multiple radios, which may enable the basestation 102 to communicate according to multiple wireless communicationtechnologies. For example, as one possibility, the base station 102 mayinclude an LTE radio for performing communication according to LTE aswell as a Wi-Fi radio for performing communication according to Wi-Fi.In such a case, the base station 102 may be capable of operating as bothan LTE base station and a Wi-Fi access point. As another possibility,the base station 102 may include a multi-mode radio which is capable ofperforming communications according to any of multiple wirelesscommunication technologies (e.g., LTE and Wi-Fi, LTE and UMTS, LTE andCDMA2000, UMTS and GSM, etc.).

As described further subsequently herein, the BS 102 may includehardware and software components for implementing features describedherein. The processor 404 of the base station 102 may be configured toimplement part or all of the methods described herein, e.g., byexecuting program instructions stored on a memory medium (e.g., anon-transitory computer-readable memory medium). Alternatively, theprocessor 404 may be configured as a programmable hardware element, suchas an FPGA (Field Programmable Gate Array), or as an ASIC (ApplicationSpecific Integrated Circuit), or a combination thereof. Alternatively(or in addition) the processor 404 of the BS 102, in conjunction withone or more of the other components 430, 432, 434, 440, 450, 460, 470may be configured to implement or support implementation of part or allof the features described herein.

FIGS. 5-8—Example Coverage Modes, Communication Flow Diagrams, and IdleMode Wakeup Timeline

As cellular communication technologies evolve, an increasing number ofcellular communication capable devices are expected to be deployed. Oneof the reasons for the continuing increase in the numbers of devicesincludes the development and spread of devices performing machine typecommunication (MTC). Such devices, which may include stationary deployeddevices, wearable devices, and/or other devices forming part of the“Internet of Things”, may commonly be designed to perform frequentand/or periodic small data transmissions.

In view of the potentially more limited expected usage scenarios formany such devices, devices primarily expected to perform MTC maycommonly be lower-complexity devices than many other common cellulardevices (e.g., handheld cellular phones, etc.), for example to reducethe size, cost of manufacture, and/or cost to the consumer of suchdevices. Accordingly, in many instances the communication capability(e.g., number and/or efficiency level of antennas, battery capability,communication range, etc.) of such devices may be relatively limited.For example, many such devices may be considered link budget limiteddevices.

This may present difficulties in a wireless communication system thatprimarily supports wireless devices with greater communicationcapability. Accordingly, at least some wireless communicationtechnologies are being revised and/or developed in a manner to supportlink budget limited devices (e.g., in addition to those wireless devicesthat are not link budget limited).

For example, at least some cellular communication systems may be capableof providing multiple coverage modes, e.g., to help accommodate wirelessdevices with different communication capabilities and/or operating indifferent radio conditions. Such coverage modes could include a normalcoverage mode (e.g., for wireless devices experiencing good radioconditions) along with one or more enhanced coverage modes (e.g., forwireless devices experiencing varying degrees of poorer radioconditions, whether as a result of inherent device capabilities, currentconditions, or some combination thereof), as one possibility. FIG. 5illustrates one example of possible different approximate coverageranges associated with different coverage modes that could be offered bya cellular base station operating in a cellular communication system,according to some embodiments. As shown, in this example, thecommunication range at which normal coverage 502 is available may besmaller than the communication range at which enhanced coverage 504 isavailable. At least in some instances, any or all of the features of thedifferent coverage modes may differ, including but not limited tocommunication bandwidth, maximum uplink throughput, maximum downlinkthroughput, and/or any of various other features.

In many instances a wireless device may predominantly or exclusivelyoperate in just one of the coverage modes offered; for example, a MTCdevice in a stationary deployment might always operate in an enhancedcoverage mode based on its particular combination of devicecharacteristics and typical radio conditions with its serving cell, asone possibility. However, as part of the increasing breadth of devicecapabilities and intended uses, at least some subset of wireless devicesmay benefit from being provided the possibility of using differentcoverage modes at different times. For example, a device may be betterserved by different coverage modes at different times based on any orall of current radio conditions, a type of communication currently beingperformed, user preference features currently enabled with respect topower saving and/or other device characteristics, etc. For such devices,providing techniques for switching between different coverage modes mayimprove operating efficiency, e.g., by extending service coverage rangeand/or reducing power consumption.

As an example, 3GPP Release 13 defines various categories of UEs,according to which category 1 and above devices may be capable ofsupporting coverage enhanced (CE) features, and may also be capable ofsupporting normal mode features.

One feature that may differ between such different coverage modes, atleast according to some embodiments, may include a type of controlchannel that is used to schedule uplink and/or downlink communicationsfor a wireless device. For example, as one possibility, the 3GPP rel. 13normal coverage mode may typically use a physical downlink controlchannel (PDCCH) that may span up to 20 MHz for paging (e.g., when inidle mode) and/or to provide uplink and downlink grants to a wirelessdevice (e.g., when in connected mode), while the 3GPP rel. 13 CE modemay typically use a MTC PDCCH (mPDCCH) that may span 1.4 MHz for pagingand/or to provide uplink and downlink grants to a wireless device. Inthis example, when a wireless device is in normal coverage mode, it maylisten for pages on the PDCCH when in idle mode, and when a wirelessdevice is in enhanced coverage mode, it may listen for pages on themPDCCH. Note that various additional or alternative control channels mayalso be possible, such as an enhanced PDCCH (E-PDCCH), among otherpossibilities. For example, such an E-PDCCH may be wider in bandwidththan the mPDCCH while also being narrower in bandwidth than the PDCCH,according to some embodiments.

Based at least in part on the different bandwidths of the PDCCH and themPDCCH (and/or other possible control channels), and also based on thecurrent radio conditions experienced, there may be substantialdetectability, effective round trip time, and/or power usage differencesfor wireless devices monitoring the PDCCH for paging information versusmonitoring the mPDCCH for paging information. Particularly for the timethat a wireless device spends in idle mode, when a wireless device maynot be regularly informing the network of its current radio conditions,there may thus be substantial potential benefit to be gained by havingthe ability to seamlessly adjust whether paging is performed on acontrol channel with features intended for normal coverage conditions,such as the PDCCH, and monitoring a control channel with featuresintended for enhanced coverage conditions, such as the mPDCCH.

Accordingly, FIG. 6 is a flowchart diagram illustrating one possibleexample of a method for performing idle mode paging for a wirelessdevice with dynamic paging channel adjustment, according to someembodiments. In various embodiments, some of the elements of the methodsshown may be performed concurrently, in a different order than shown,may be substituted for by other method elements, or may be omitted.Additional method elements may also be performed as desired.

Aspects of the method of FIG. 6 may be implemented by a wireless device,such as a UE 106 or 107 illustrated in and described with respect toFIGS. 1-3 and/or a BS 102 such as illustrated in and described withrespect to FIGS. 1, 2, and 4, or more generally in conjunction with anyof the computer systems or devices shown in the above Figures, amongother devices, as desired. Note that while at least some elements of themethod of FIG. 6 are described in a manner relating to the use ofcommunication techniques and/or features associated with LTE and/or 3GPPspecification documents, such description is not intended to be limitingto the disclosure, and aspects of the method of FIG. 6 may be used inany suitable wireless communication system, as desired. As shown, themethod may operate as follows.

In 602, the UE and the BS may establish a radio resource control (RRC)connection. The RRC connection may be established after the UE initiallycamps on a serving cell provided by the cellular base station, accordingto some embodiments. The serving cell may provide cellular communicationservice according to a wireless communication technology (or “radioaccess technology” or “RAT”), such as LTE, 5G-NR, UMTS, CDMA2000, etc.To camp on the serving cell, the wireless device may detect that theserving cell exists, obtain timing synchronization and decode systeminformation for the serving cell, and attach to the cell (e.g., byperforming an attachment procedure), according to some embodiments. TheRRC connection may be established by way of a random access channel(RACH) procedure performed while operating in an idle mode, according tosome embodiments, or in any of various other possible manners.

While in the RRC connected mode, the UE may operate in a normal coveragemode or an enhanced coverage mode. According to some embodiments, duringa normal mode RRC connection, the PDCCH may be used for physical layer(also referred to as layer 1 or L1) signaling to schedule uplink anddownlink grants, uplink hybrid automatic repeat request (HARQ)transmission may be synchronous HARQ, and downlink HARQ transmission maybe asynchronous HARQ. Additionally, during a CE mode RRC connection, themPDCCH may be used for physical layer signaling to schedule uplink anddownlink grants, uplink HARQ transmission may by asynchronous HARQ, anddownlink HARQ transmission may be asynchronous HARQ.

The serving cell may provide the wireless device with a communicationlink to a cellular network, such as a core network of a cellular serviceprovider (e.g., with which a user of the wireless device may have asubscription and/or other agreement to provide cellular service). Whenoperating in connected mode with the serving cell, the cellular networkmay thus provide connectivity between the user device and variousservices and/or devices coupled to the cellular network, such as otheruser devices, a public switched telephone network, the Internet, variouscloud-based services, etc. A variety of possible data types, withdifferent characteristics, may be transmitted via the serving cell. Inaddition, various signaling messages may be exchanged at various timesto establish, maintain, reconfigure, and/or otherwise provide signalingfunctionality between the wireless device and the serving cell.

Eventually, in 604, the BS and the UE may release the RRC connection.When the RRC connection is released, the network MME supporting the BSand the UE may save the status of the UE with respect to whether the UEis in normal coverage or enhanced coverage in the UE's MME context.Thus, as one (e.g., default) option, when subsequently the network has apaging message for the UE, the network may attempt to page the UE usingthe control channel (e.g., PDCCH or mPDCCH) associated with the UE'smost recent coverage mode. However, in many circumstances (e.g., due toUE mobility, load, and/or other factors), the actual coverage conditionsof the UE may change while in idle mode, such that the UE mightsometimes be in normal coverage conditions while the network stillconsiders the UE to be in enhanced coverage mode, or in enhancedcoverage conditions while the network still considers the UE to be innormal coverage mode.

When a UE moves from enhanced coverage conditions to normal coverageconditions, the UE may still be able to decode pages on the mPDCCH, butwhen a UE moves from normal coverage conditions to enhanced coverageconditions, the UE may be more likely to miss paging attempts performedusing the PDCCH. One possible solution for this could be for the UE toupdate the network to change its coverage mode status when coverageconditions change from normal to enhanced (e.g., by establishing a RRCconnection and performing a tracking area update (TAU), as onepossibility), so the MME normal/enhanced mode status can be updated, andsubsequent pages can be provided using the mPDCCH. However, such asolution introduces additional signaling load to the network.

As another possible solution, it may be possible for the network tobegin paging a UE that is in idle mode using one control channel, andautomatically switch to the other control channel if the initialattempt(s) are unsuccessful. This may allow the network to accommodateUEs that move between different coverage conditions when in idle modewithout requiring any additional signaling.

Thus, in 606, the BS may page the UE using a first control channel, thenmay page the UE using a second control channel if the attempt(s) to pagethe UE using the first control channel are unsuccessful. The firstcontrol channel may be the control channel associated with the coveragemode that the network expects that the UE is in. For example, if the UEis in the enhanced coverage mode (e.g., according to the MME context forthe UE), the control channel associated with the enhanced coverage mode(e.g., the mPDCCH) may initially be used to attempt to provide a pagingindication to the UE, while if the UE is in the normal coverage mode(e.g., according to the MME context for the UE), the control channelassociated with the normal coverage mode (e.g., the PDCCH) may initiallybe used to attempt to provide a paging indication to the UE.Alternatively, the first control channel may always be the controlchannel associated with the normal coverage mode, or may always be thecontrol channel associated with the enhanced coverage mode, if desired.The BS may perform multiple attempts to page the UE using the firstcontrol channel if a first attempt is unsuccessful, according to someembodiments, e.g., up to a specified maximum number of attempts for thefirst control channel.

If the attempt(s) to page the UE using the first control channel areunsuccessful (e.g., the UE does not respond), the BS may perform one ormore attempts to page the UE using the second control channel. Thesecond control channel may be the control channel not associated withthe coverage mode that the network expects that the UE is in. Forexample, if the UE is in the enhanced coverage mode (e.g., according tothe MME context for the UE), the control channel associated with thenormal coverage mode (e.g., the PDCCH) may be the second control channelused to attempt to provide a paging indication to the UE, while if theUE is in the normal coverage mode (e.g., according to the MME contextfor the UE), the control channel associated with the enhanced coveragemode (e.g., the mPDCCH) may be the second control channel used toattempt to provide a paging indication to the UE. Alternatively, thesecond control channel may always be the control channel associated withthe enhanced coverage mode, or may always be the control channelassociated with the normal coverage mode (e.g., such that the secondcontrol channel is a different control channel than the first controlchannel), if desired. The BS may perform multiple attempts to page theUE using the second control channel if a first attempt is unsuccessful,according to some embodiments, e.g., up to a specified maximum number ofattempts for the second control channel.

According to some embodiments, the BS may increase the aggregation leveland/or power boost to increase the UE's decoding success rate for eachsuccessive attempt to page the UE on the first control channel and/or onthe second control channel. For the mPDCCH, the number of repetitionsused may also or alternatively be increased for successive attempts topage the UE, at least in some instances.

Note that the BS may be attempting to page the UE based on an indicationto page the UE that the BS receives from a MME. The indication to pagethe UE may include an indication of the coverage mode of the UE, basedon which the BS may determine on which control channel to initiallyattempt to page the UE. In some embodiments, the MME may also indicatehow many previous attempts to page the UE have occurred. In such a case,the BS may determine on which control channel to attempt to page the UEbased at least in part on the number of previous attempts to page the UEthat have occurred. For example, if the BS would normally initially pagethe UE using the first control channel for two attempts, but two (ormore) attempts to page the UE have previously been made (e.g., by otherbase stations in the vicinity), the BS may skip attempting to page theUE using the first control channel, and may instead attempt to page theUE using the second control channel.

In 608, the UE may attempt to decode the first and/or second controlchannel during one or more paging occasions. At least according to someembodiments, the paging occasion subframe for a UE may be determined inthe same manner for both control channels on which paging can occur. Forexample, the paging occasion subframe in idle discontinuous reception(DRX) may be based on the international mobile subscriber identity(IMSI) of a UE for both paging on the PDCCH and the mPDCCH, according tosome embodiments.

According to some embodiments, the UE may first attempt to decode thecontrol channel associated with the normal coverage mode during a pagingoccasion. For example, the PDCCH may generally be located in the first 3orthogonal frequency division multiple access (OFDMA) symbols of asubframe, so the UE may first attempt to decode its paging radio networktemporary identifier (P-RNTI) on the PDCCH. If the P-RNTI is decoded onthe PDCCH, this may serve as a paging indication (i.e., the UE's UE_IDmay be paged on the PDCCH), and the UE can decode the PDSCH in the samesubframe to obtain the paging message. Note that in this (successful)case, the UE may not need to attempt to decode the control channelassociated with the enhanced coverage mode.

If decoding the control channel associated with the normal coverage modeis unsuccessful (e.g., the P-RNTI is not decoded on the PDCCH), however,the UE may attempt to decode the control channel associated with theenhanced coverage mode during the same paging occasion. For example, themPDCCH may generally be located on a 6PRB Paging Narrow Band specific tothe UE (e.g., which may also be based on its IMSI) on the OFDMA symbolsother than those symbols occupied by the PHICH and PDCCH in the samesubframe, such that it may be possible to attempt to decode the mPDCCHin the same subframe as a UE attempts to decode the PDCCH. Note that theUE may be able to switch its RF front end from a wideband configuration(e.g., up to 20 MHz) to a narrowband configuration (e.g., 1.4 MHz or 6physical resource blocks (PRBs)) and a single antenna configuration todecode the mPDCCH after unsuccessfully attempting to decode the P-RNTIon the PDCCH.

If the P-RNTI is not decoded on the mPDCCH in the first subframe, the UEmay compare the signal strength for the mPDCCH with a signal strengththreshold. For example, as one possibility, the UE may determine whetherthe mPDCCH log likelihood ratio (LLR) signal to noise ratio (SNR) isgreater than or less than a certain threshold. The threshold value maybe selected by the UE, or indicated (e.g., in configuration information)by the network, or specified in standards documents, according tovarious embodiments. The threshold value may be selected as a valueabove which a UE may have a high likelihood of being able tosuccessfully decode the P-RNTI if provided on the mPDCCH. Thus, if thesignal strength (e.g., LLR SNR) is higher than the threshold, and the UEdoes not successfully decode a paging indication on the control channelassociated with the enhanced coverage mode (e.g., the P-RNTI is notdocoded on the mPDCCH), the UE may determine that there is no pagingindication from the cellular base station for the paging occasion. Inthis case, the UE may enter a sleep mode, e.g., until the next paging orother wakeup occasion for the UE.

If, however, the signal strength (e.g., LLR SNR) is lower than thethreshold, the UE may also attempt to decode the control channelassociated with the enhanced coverage mode in the subsequent subframe(e.g., the second subframe of the paging occasion). Additionally, the UEmay perform soft combining of the control channel associated with theenhanced coverage mode received in the first subframe of the pagingoccasion with the control channel associated with the enhanced coveragemode received in the second subframe of the paging occasion, e.g., toincrease the LLR SNR and increase the likelihood of successfullydecoding a paging indication (if provided). Depending on the result ofthis attempt to decode the control channel (e.g., successful orunsuccessful decoding and the signal strength after soft combining), theUE may determine that there is no paging indication from the cellularbase station for the paging occasion (e.g., if unsuccessful at decodingand signal strength after soft combining is above the signal strengththreshold), or may continue to attempt to decode the control channelassociated with the enhanced coverage mode in subsequent subframes(e.g., continuing to use soft combining to increase effective signalstrength), potentially up to a maximum configured number of repetitionsof the control channel associated with the enhanced coverage mode (e.g.,if unsuccessful at decoding and signal strength after soft combining isstill below the signal strength threshold), or may attempt to decode thePDSCH in a specified subsequent subframe (or over multiple subframes,e.g., depending on channel conditions and the number of PDSCHrepetitions used by the BS) to obtain the paging message (e.g., ifsuccessful at decoding the P-RNTI on the mPDCCH).

Thus, a UE may generally be able to attempt to decode either or both ofthe control channel associated with the normal coverage mode and thecontrol channel associated with the enhanced coverage mode on eachpaging occasion. This may provide a high likelihood that a UE is able toreceive paging messages in a variety of channel conditions withoutburdening the network with additional signaling to update the status ofthe UE as its channel conditions change while in idle mode. For example,in a 3GPP context, for category 1 and above UEs with enhanced coveragemode capability, if an eNodeB can page a UE on both the PDCCH and themPDCCH, and the UE can decode both the PDCCH and mPDCCH on the pagingoccasion subframe(s) in each of its idle DRX cycles, the UE may be ableto forego providing a TAU when the UE moves from normal coverageconditions to enhanced coverage conditions, such that no extra signalingload may be placed on the network.

Note that although a UE may attempt to decode both control channels onpaging occasions, as described above herein, under some conditions, a UEmay also be capable of choosing to selectively not decode one of thecontrol channels on a paging occasion under some conditions. Forexample, a UE that is aware that it is in enhanced coverage conditionsmay choose not to attempt to decode the PDCCH, since based on thecoverage conditions the UE might be unlikely to succeed at decoding thePDCCH. Similarly, a UE may choose not to perform a check for whethersignal strength is above the signal strength threshold after anunsuccessful attempt to decode the mPDCCH if desired, and may simplyproceed to attempt to decode the mPDCCH at the next repetition/subframe,until successful or until the maximum number of mPDCCH repetitions isreached, e.g., depending on the coverage conditions for the UE.Alternatively, a UE may be configured to always monitor the PDCCH first,and/or to always perform a check for whether signal strength is abovethe signal strength threshold after an unsuccessful attempt to decodethe mPDCCH, regardless of the current coverage conditions for the UE, ifdesired.

As previously discussed herein, for a UE that is technically capable ofdecoding paging indications on the PDCCH and on the mPDCCH while in idlemode, there may (e.g., depending on coverage conditions) be scenarios inwhich the UE can reliably decode paging indications and messagesprovided by way of the PDCCH or provided by way of the mPDCCH, as wellas scenarios in which the UE can decode paging indications and messagesprovided by way of the mPDCCH but cannot reliably decode pagingindications and messages provided by way of the PDCCH. For example, innormal coverage, a UE may be able to reliably decode a P-RNTI on thePDCCH and a paging message on the PDSCH in the same subframe, and the UEmay also be able to reliably decode a P-RNTI on the mPDCCH and a pagingmessage on the PDSCH in one subframe, such that paging the UE on eitherof the PDCCH or the mPDCCH may be efficient for the UE and its servingbase station. In contrast, in extended coverage, a UE may possibly notbe able to decode a P-RNTI on the PDCCH and a paging message on PDSCH(e.g., due to lower SNR and/or reference signal received power (RSRP));but due to mPDCCH and PDSCH repetition in CE mode, the UE may be able todecode a paging indication on the mPDCCH, such that paging the UE on themPDCCH may be efficient for the UE and its serving base station.

Since a base station may not know a UE's radio condition when the UE isin idle mode, the base station may always page UEs on the mPDCCH as anefficient method for both UEs and the base station. However, due to NWloading and capacity related reasons, among various possible reasons, abase station may not always be able to page UEs in its cell using onlythe mPDCCH. When such conditions are present, the base station mayinstead perform paging using a different arrangement, such as anarrangement similar to the paging arrangement described herein withrespect to FIG. 6. For example, under some circumstances, the basestation may utilize an arrangement in which the base station initiallyattempts to page a UE using the PDCCH, then after a number ofunsuccessful paging attempts, the base station switches to attempting topage the UE on the mPDCCH.

FIG. 7 is a flowchart diagram illustrating one possible example of sucha method for performing idle mode paging for a wireless device withdynamic paging arrangement selection, according to some embodiments. Invarious embodiments, some of the elements of the methods shown may beperformed concurrently, in a different order than shown, may besubstituted for by other method elements, or may be omitted. Additionalmethod elements may also be performed as desired.

Aspects of the method of FIG. 7 may be implemented by a wireless device,such as a UE 106 or 107 illustrated in and described with respect toFIGS. 1-3 and/or a BS 102 such as illustrated in and described withrespect to FIGS. 1, 2, and 4, or more generally in conjunction with anyof the computer systems or devices shown in the above Figures, amongother devices, as desired. Note that while at least some elements of themethod of FIG. 7 are described in a manner relating to the use ofcommunication techniques and/or features associated with LTE and/or 3GPPspecification documents, such description is not intended to be limitingto the disclosure, and aspects of the method of FIG. 7 may be used inany suitable wireless communication system, as desired. As shown, themethod may operate as follows.

In 702, the BS may determine a paging arrangement to use when paging UEsserved by the BS. The possible paging arrangements may include any ofvarious possible paging arrangements. One possible (“first”) pagingarrangement may include always performing paging using a certain controlchannel (e.g., a control channel associated with enhanced coverageconditions, such as the mPDCCH in LTE). Another possible (“second”)paging arrangement may include initially performing paging using a firstcontrol channel (e.g., a control channel associated with normal coverageconditions, such as the PDCCH in LTE), and subsequently performingpaging using a second control channel (e.g., a control channelassociated with enhanced coverage conditions, such as the mPDCCH in LTE)if paging using the first control channel is unsuccessful. The BS mayalso or alternatively select from any of various other possible pagingarrangements, as desired.

The paging arrangement may be selected based on the current loadconditions of the BS, the capacity and/or other characteristics of theBS, and/or any of various other possible considerations. For example, asone possibility, if current loading of the BS is less than the capacityof the BS by a sufficient amount (e.g., if the current loading relativeto the capacity is below a first loading threshold), the BS may selectthe first paging arrangement, while if current loading of the BS is notless than the capacity of the BS by a sufficient amount (e.g., if thecurrent loading relative to the capacity is not below the first loadingthreshold), the BS may select the second paging arrangement.Alternatively, multiple loading thresholds may be used, e.g., if ahysteresis between the first paging arrangement and the second pagingarrangement is desired.

In 704, the BS may broadcast an indication of the selected pagingarrangement. The indication may be broadcast as part of systeminformation, for example in a system information block (SIB), such as aSIB2 (e.g., which may include paging control channel (PCCH)configuration information) according to LTE. For example, along withexisting information related to paging on the mPDCCH (e.g., pagingnarrow bands, mPDCCH number of repetitions, etc.), an indication ofwhether all UEs with CE mode capability should always listen to themPDCCH for paging may be provided.

As shown, the UE may receive the broadcast indication of the selectedpaging arrangement. In 706, the BS may further attempt to page the UEaccording to the indicated paging arrangement.

In 708, the UE may attempt to decode one or both of a first controlchannel or a second control channel during its paging occasion(s), basedon the indicated paging arrangement and/or based on current coverageconditions for the UE.

For example, if the UE is camping on the cell provided by the BS, and ifthe broadcast indication of the paging arrangement includes a TRUEindication for the “always page on mPDCCH” field, the UE may listen forpages on the mPDCCH, potentially without listening for pages on thePDCCH, e.g., regardless of whether the UE is experiencing normalcoverage conditions or enhanced coverage conditions.

Alternatively, if the broadcast indication of the paging arrangementincludes a FALSE indication for the “always page on mPDCCH” field, theUE may listen to both the PDCCH and the mPDCCH if the UE is in normalcoverage conditions, or, if the UE is in enhanced coverage conditions,the UE may only listen for pages on the mPDCCH.

Note that the base station may determine to change the pagingarrangement used, e.g., at a later time, based on changing cell loadingconditions and/or other consideration. For example, after initiallydetermining to use the first paging arrangement based on loadingconditions being below a loading threshold associated with the firstpaging arrangement, the BS may later determine that loading conditionshave increased above a loading threshold associated with the secondpaging arrangement, and may determine to switch to the second pagingarrangement. In this case, the BS may provide a broadcast indication ofthe newly selected paging arrangement (e.g., at the next opportunity toupdate the SIB2, if the broadcast indication is provided in the SIB2),and once the BS has indicated the newly selected paging arrangement, theBS may subsequently perform paging according to the newly selectedpaging arrangement. Additionally, UEs receiving the broadcast indicationof the newly selected paging arrangement may likewise modify theirpaging behavior in accordance with the indicated paging arrangement.

As noted previously herein, according to some embodiments, a BS mayprovide some configured number of repetitions of each of the mPDCCH(e.g., used to transmit paging indications) and the PDSCH (e.g., used totransmit paging messages) when a UE is operating in enhanced coveragemode. Since, at least in some instances, it may be possible for a BS toattempt to page a UE using the mPDCCH when the UE has moved tonormal/good channel conditions, this may result in a UE successfullydecoding the mPDCCH and PDSCH using fewer than the configured number ofrepetitions, including potentially using only the first transmission ofeach. In this case, the UE may be able to enter a sleep mode between themPDCCH and PDSCH subframes. Even in bad channel conditions, in someinstances a UE may enter sleep mode between the mPDCCH and PDSCHsubframes, e.g., if enough of a gap exists between the subframe in whichthe UE successfully decodes the mPDCCH transmission and the subframethat it is scheduled to receive the PDSCH transmission from the network.

FIG. 8 illustrates an exemplary possible mPDCCH/PDSCH transmissionarrangement with various possible idle mode wakeup timelines accordingto which a UE could operate, according to some embodiments. Inparticular, the scenarios illustrated may represent possible idle modewakeup timelines for a UE that is in channel conditions sufficient tosuccessfully decode the mPDCCH and PDSCH using a single transmission ofeach.

In ‘scenario 1’, the sleep duration can be adapted based on the decodeperformance of the mPDCCH and the estimated channel conditions (e.g.,SNR, RSRP, RSRQ, etc.). The UE can then project its expected PDSCHdecode performance, and then can wakeup only for the last x repetitions(e.g., where x=1 in the illustrated example) of the PDSCH transmissions.Scenario 1 may be well suited for situations when a medium or largenumber of repetitions are being provided while the UE is in good channelconditions, for example since it may allow the UE to enter a deeper(‘lowest-power’) sleep, and may thus reduce UE power consumption in suchsituations.

In ‘scenario 2’, the UE may enter a (‘low-power’) sleep mode aftersuccessful decoding of the mPDCCH (e.g., after 1 transmission in theillustrated example, although in other instances different numbers ofrepetitions may be required), and may wakeup for the first repetition ofthe PDSCH. Once the PDSCH is successfully decoded, the UE may re-enterthe sleep mode during the remaining PDSCH repetition subframes. Scenario2 may be well suited for situations when a small number of repetitionsare being provided while the UE is in good channel conditions, or when alarge number of repetitions are being provided while the UE is in badchannel conditions and it may take the UE several repetition subframesto successfully decode the mPDCCH and PDSCH, for example since in suchsituations the gap duration for sleep may be too small to enter thedeeper (‘lowest-power’) sleep state in any case.

According to some embodiments, in the ‘lowest-power’ sleep mode, the UEmay be able to power off more power-consuming radio and basebandcomponents than may be possible or preferred for the ‘low-power’ sleep;in the ‘low-power’ sleep mode, the UE may be able to power off someradio and baseband components, but other components may remain poweredon, e.g., as the sleep duration may be shorter than for the‘lowest-power’ sleep mode.

Another possible consideration with respect to idle mode wakeup timingfor paging occasions may relate to dual subscriber identity module (SIM)dual standby (DSDS) systems. In a DSDS system, a UE may include twoSIMs, and may be capable of concurrently operating in idle mode usingboth of the SIMs. Thus, a UE could be attached to a network using oneRAT (e.g., GSM, UMTS (W-CDMA or TDS-CDMA), CDMA2000, LTE, NR, etc.)while also attached to a network using another (same or different) RAT.In such a scenario, there may be a possibility that both RATs' pagingoccasion subframes conflict/collide (e.g., occur at the same time) forthe UE.

In such a scenario, if one of the RATs provides paging information usinga control channel that provides some number of repetitions, such as themPDCCH according to LTE R13, the UE may be able to manage its idle modewakeup timing such as to mitigate the effect of the paging occasionconflict between the RATs. For example, consider a DSDS UE that includesan LTE SIM in normal coverage conditions but operating in enhancedcoverage mode, such that paging indications are provided on the mPDCCHwith a repetition level N and paging messages are provided on the PDSCHwith a repetition level M for that SIM. Consider further that the UE hasa conflict between the paging occasions of its LTE SIM and the RAT ofits other SIM. Such a UE may choose to observe the paging occasion forthe other RAT, and to begin attempting to decode the mPDCCH at any ofthe N subframes in which a repetition of the mPDCCH is provided thatdoes not conflict with the paging occasion subframe of the other RAT.Alternatively, if the paging occasion conflict occurs between the pagingoccasion subframe of the other RAT and a subframe on which the pagingmessage is provided on the PDSCH (e.g., after a P-RNTI is successfullydecoded on the mPDCCH, indicating that there is a paging message for theUE), the UE may choose to begin attempting to decode the PDSCH at any ofthe M subframes in which a repetition of the PDSCH is provided that doesnot conflict with the paging occasion subframe of the other RAT.

Thus, a UE may be configured to modify its paging occasion wakeup and/ormonitoring timing for a RAT that provides multiple paging indicationand/or message repetitions in response to detecting a paging occasionconflict with another RAT when the UE is operating in a DSDS mode, ifdesired. This may allow the UE to effectively observe the pagingoccasions for both of its RATs despite the paging occasion conflict, atleast according to some embodiments.

Furthermore, at least in some instances, a DSDS UE may be configured tochoose to operate in an enhanced coverage mode with respect to a SIM RAT(e.g., an LTE SIM) that is so capable based at least in part on being aDSDS UE, e.g., to allow the UE to make use of the control channelrepetition level provided when in the enhanced coverage mode, topotentially save DSDS system power consumption, and/or for any ofvarious other reasons. Such a DSDS UE might make such a selectionfurther based on the UE's power condition/battery level, currentlyactive application(s) (e.g., VoLTE, low throughput or high throughputapplications, etc.), and/or any of various other considerations,according to some embodiments. Note further that such a DSDS UE may beconfigured to actively manage whether the UE operates in the enhancedcoverage mode or the normal coverage mode when in idle mode and/or whenin connected mode.

Additional Information

The following information includes possible details of LTE release 13enhanced coverage mode characteristics and parameters, is provided forexemplary illustrative purposes, and is not intended to be limiting tothis disclosure as a whole.

A wireless device may be categorized according to its device categorywith respect to LTE, according to some embodiments. For example,consider a category 1 LTE device, e.g., a device that is UL Category 1and DL category 1. For such a device, a e-HARQ-pattern-FDD-r12 parametermay define whether the UE supports an enhanced HARQ pattern for TTIbundling operation for FDD, e.g, with 4 TTI bundling, 3 HARQ processes,and round trip time (RTT) of 12 ms. A ce-ModeA-r13 parameter may definewhether the UE supports operation in CE mode A and PRACH CE level 0 and1 at Random Access. A intraFreqA3-CE-ModeA-r13 parameter may definewhether the UE when operating in CE mode A supports eventA3 for intraneighboring cells in normal coverage and CE mode A. AintraFreqH0-CE-ModeA-r13 parameter may define whether the UE whenoperating in CE mode A supports intra handover to target cell in normalcoverage and CE mode A.

A new 32 bits signature in a MIB provided by a cell may be used toindicate if CE SIM is scheduled and its transport block size and numberof repetitions. Such a signature may indicate that the cell supports CEfeatures defined by 3GPP R13; a signature value of 0 may mean that theCE feature is not supported.

If CE features are supported by the cell, a CE SIB1 for CoverageEnhancement may be provided by the cell. A larger SI window length andrepetition pattern may be used for CE SIBs. A narrow band (e.g.,contiguous 6PRBs) and transport block size may also be used for CE SIBs.Additionally, a frequency hopping configuration may be used for CE SIBs.A CE SIB2 for Coverage Enhancement may also be provided. The CE SIBs mayindicate CE PRACH configurations and CE mPDCCH/PDSCH/PUSCH/PCH commonconfigurations.

Each CE level supported by a serving cell may be associated with a setof PRACH resources for transmission of Random Access Preambles. The CElevel for a UE may be selected based on serving cell RSRP measurementand CE SIB2 rsrp-ThresholdsPrachInfoList. The maximum number of preambletransmission attempts (3/4/5/6/7/8/10) per each CE level may be providedby the CE SIB2. The number of repetitions (1/2/4/8/16/32/64/128)required for preamble transmission per attempt for each CE level mayalso be provided by theCE SIB2. Additionally, the narrow bands tomonitor for the mPDCCH for a RAR in each CE level, the number ofrepetitions for mPDCCH common search space for RAR, msg3 and msg4, andthe RA response window size and contention resolution Timer per CE levelmay all be provided by the CE SIB2.

If a UE is in enhanced coverage, it shall select a PRACH preamble forrandom access based on its corresponding CE level. The UE may transmit apreamble with corresponding number of repetitions, RA_RNTI, preamble indand target power.

If the UE fails on max number of random access attempts on one CE level,it shall try to random access on next CE level.

The msg3 PUSCH repetition number may be indicated in the RAR receivedfrom the network.

A parameter PUCCH-NumRepetitionCE may provide a number of PUCCHrepetitions for PUCCH format 1/1a/2/2a/2b for CE mode A.

A parameter PUCCH-numRepetitionCE-msg4-level0/1/2/3 may provide a numberof repetitions for PUCCH carrying HARQ response to PDSH containing msg4for PRACH CE level 0/1/2/3.

One paging occasion (PO) in a CE mode may include a subframe in which aP-RNTI is transmitted on the mPDCCH. The subframe may be determined bythe UE based on its IMSI, DRX cycle, and number of paging narrow bands(Nn) provided in CE SIB2.

The mPDCCH carrying a PO can be repeated multiple times, e.g., asdefined by the parameter mPDCCH-NumRepetition-Paging-R13 in CE SIB2.

Information on the coverage enhancement (CE) level, if available for theUE, may be provided transparently by the serving eNB to the MME attransition to ECM_IDLE together with the respective cell identifier, andmay be provided to the E-UTRAN during paging. Paging attempt informationmay always be provided to all paged eNBs for UEs for which theinformation on the coverage enhancement level has been received.

If paging attempt information is included in the paging message, eachpaged eNB may receive the same information during a paging attempt. Thepaging attempt count may be increased by one at each new paging attempt.The next paging area scope, when present, indicates whether the MMEplans to modify the paging area currently selected at next pagingattempt. If the UE has changed its mobility state to ECM CONNECTED thePaging Attempt Count is reset.

A PUSCH transmission in an enhanced coverage mode can be in a N-subframeTTI bundle indicated by mPDCCH. A parameterPUSCH-maxNumRepetitionCEmodeA-r13, having a value of 8/16/32, mayindicate a maximum value to indicate the set of PUSCH repetition numbersfor CE mode A, e.g., among the following possibilities: {1, 2, 4, 8},{1, 4, 8, 16}, {1, 4, 16, 32}. A parameterPUSCH-maxNumRepetionCEmodeB-r13, having a value of 192/256/ . . . /2048,may indicate a maximum value to indicate the set of PUSCH repetitionnumbers for CE mode B. The PUSCH bandwidth may be limited to 6PRB,according to some embodiments. Uplink HARQ operation may be asynchronousfor UEs in enhanced coverage except for the receptions within a bundle.

A PDSCH transmission in an enhanced coverage mode can be in a N-subframeTTI bundle indicated by mPDCCH. A parameterPDSCH-maxNumRepetionCEmodeA-r13, having a value of 8/16/32, may indicatea maximum value to indicate the set of PDSCH repetition numbers for CEmode A, e.g., among the following possibilities: {1, 2, 4, 8}, {1, 4, 8,16}, {1, 4, 16, 32}. A parameter PDSCH-maxNumRepetionCEmodeB-r13, havinga value of 192/256/ . . . /2048, may indicate a maximum value toindicate the set of PDSCH repetition number for CE mode B. The PDSCHbandwidth may be limited to 6PRB, according to some embodiments.

The mPDCCH provided in an enhanced coverage mode may utilize arepetition level among the following repetition levels: {1, 2, 4, 8, 16,32, 64, 128, 256}. The mPDCCH aggregation level may be among thefollowing aggregation levels: {1, 2, 4, 8, 16, 12, 24}. The mPDCCHbandwidth may be limited to 6PRB, according to some embodiments.

An existing NW configuration for VoLTE may include PUSCH 4TTIB, 4HARQ,HARQ RTT 16 ms, with one/two audio packet bundling, TBS 208 bits/328bits, segment 144/176 bits, 4 HARQ transmissions. An increase in HARQtransmissions from 4 to 7 could result in a link budget gain (e.g., ˜2dB, as one possibility).

A possible mPDCCH/PUSCH configuration in CE mode A could include PUSCH8TTIB, 3 HARQ, HARQ RTT 24 ms, mPDCCH with 4 repetitions. For one audiopacket bundling, TBS 208 bits, segment 144/176 bits, 5/6/7 HARQtransmissions could be used. For two audio packet bundling, TBS 328bits, segment 144/176 bits, 5/6/7 HARQ transmissions could be used. Thismay provide a potential UL link budget gain of ˜4-5 dB, as onepossibility.

Another possible mPDCCH/PUSCH in CE mode A could include PUSCH 8TTIB, 2HARQ, HARQ RTT 16 ms, mPDCCH with 2 repetitions. For one audio packetbundling, TBS 208 bits, segment 144/176 bits, HARQ 8/9/10 transmissionscould be used. For two audio packet bundling, TBS 328 bits, segment144/176 bits, HARQ 8/9/10 transmissions could be used. This may providea potential UL link budget gain of ˜6 dB-7 dB, as one possibility.

Another possible mPDCCH/PUSCH in CE mode A could include PUSCH 4TTIB, 3HARQ, HARQ RTT 12 ms, mPDCCH with 2 repetitions. For one audio packetbundling, TBS 208 bits, segment 144/176 bits, HARQ 10/11/12transmissions could be used. For two audio packet bundling, TBS 328bits, segment 144/176 bits, HARQ 10/11/12 transmissions could be used.This may provide a potential UL link budget gain of ˜4 dB-5 dB, as onepossibility.

For a UE with category 1 and above, when in a coverage beyond normalcoverage, in order to not go out-of-service (OOS), it may be possiblefor a wireless device to dynamically utilize a coverage enhancementfeature if it is supported by eNodeB. As part of such techniques, when acell is selected as serving cell to camp on, a UE may determine if thecell supports 3GPP R13 coverage enhancement feature by checking if theCE signature present in MIB. If CE is supported on the serving cell, theUE may store CE SIBs for CE level thresholds, CE PRACH and mPDCCHconfigurations.

When in idle mode, based on serving cell measurements, the UE maydetermine if it is in normal coverage or enhanced coverage and itscorresponding CE level. If the UE is entering enhanced coverage fromnormal coverage, UE may utilize the configuration information from theCE SIBs to establish a mobility management connection (perform a TAU orsend any other MM message) to update its MME to switch to CE mode idlepaging. The UE may switch to listen to the mPDCCH for idle paging. Whenthe MME eventually pages the UE, the MME may send the UE's CE levelinformation and page attempt count information to a group of eNodeBs.Each eNodeB in the group may thus determine to page the UE on the mPDCCHif the UE is in enhanced coverage, and may otherwise page the UE on thePDCCH. Additionally, the UE's intra/inter cell re-selection may be basedon cell selection criterion S for enhanced coverage (e.g., instead ofcell selection criterion S for normal coverage).

If the UE is entering normal coverage from enhanced coverage, the UE maycontinue to listen to the mPDCCH for idle paging, or may establish amobility management connection (e.g., perform a TAU) to update its MMEto switch to normal mode idle paging, in which case the UE may switch tolisten to the PDCCH for idle paging. Additionally, its intra/inter cellre-selection may be based on cell selection criterion S for normalcoverage (e.g., instead of cell selection criterion S for enhancedcoverage).

When establishing a RRC connection, if the UE is in normal coverage, itmay select a PRACH preamble for normal coverage for performing a randomaccess procedure. If the UE is in enhanced coverage, it may select aPRACH preamble from the corresponding enhanced coverage level forperforming a random access procedure.

When exiting a RRC connection, if the UE is in normal coverage, it mayenter idle mode in normal coverage, read normal SIBs, and listen to thePDCCH for idle paging. If the UE is in enhanced coverage, it may enteridle mode in enhanced coverage, read CE SIBs, and listen to the mPDCCHfor idle paging. Alternatively, as described previously herein, ifdesired, a UE may listen to both the PDCCH and the mPDCCH for idle modepaging, and the network may attempt to page the UE on one of the PDCCHor mPDCCH (e.g., depending on the coverage mode of the UE) initially,and may switch to attempting to page the UE on the other control channelafter one or more unsuccessful attempts on the initial control channel.

During an RRC connection, if the UE is entering enhanced coverage fromnormal coverage, the UE may use a PRACH preamble from its correspondingCE level to re-establish the RRC connection; or, alternatively, the NWmay reconfigure the RRC connection to use the mPDCCH, e.g., based on aUE triggered measurement report. If the UE is entering normal coveragefrom enhanced coverage, the UE may use a PRACH preamble for normalcoverage to re-establish the RRC connection; or, alternatively, the mayNW reconfigure the RRC connection to use the PDCCH, e.g, based on a UEtriggered measurement report. The network may also perform same-cellhandover using a dedicated PRACH preamble for enhanced coverage toswitch the UE to use of the mPDCCH during the RRC connection; or,conversely, the network may use a dedicated PRACH preamble for normalcoverage to switch the UE to use of the PDCCH during the RRC connection.Further, the NW may perform NW triggered HO from a cell in enhancedcoverage to a cell in normal coverage, or a cell in normal coverage to acell in enhanced coverage. The UE may trigger RRC re-establishment to acell in normal coverage from a cell in enhanced coverage, or from a cellin normal coverage to a cell in enhanced coverage. Additionally, thenetwork may use the RRC connection release message to indicate to a UEwhether to operate in normal coverage mode or enhanced coverage modeafter the RRC connection is released.

In the following further exemplary embodiments are provided.

One set of embodiments may include a method, comprising: by a wirelessdevice: establishing a radio resource control (RRC) connection with acellular base station; releasing the RRC connection with the cellularbase station, wherein the wireless device is in one of a normal coveragemode or an enhanced coverage mode when releasing the RRC connection;monitoring a control channel associated with the normal coverage modeduring a paging occasion; and monitoring a control channel associatedwith the enhanced coverage mode during the paging occasion if a pagingindication is not successfully decoded on the control channel associatedwith the normal coverage mode.

According to some embodiments, the method further comprises, if a pagingindication is not successfully decoded on the control channel associatedwith the enhanced coverage mode during a first subframe of the pagingoccasion: determining a signal strength of the control channelassociated with the enhanced coverage mode during the first subframe ofthe paging occasion; determining that there is no paging indication fromthe cellular base station for the paging occasion if the signal strengthof the control channel associated with the enhanced coverage mode duringthe first subframe of the paging occasion is above a signal strengththreshold; and attempting to decode the control channel associated withthe enhanced coverage mode during a second subframe of the pagingoccasion if the signal strength of the control channel associated withthe enhanced coverage mode during the first subframe of the pagingoccasion is below the signal strength threshold.

According to some embodiments, attempting to decode the control channelassociated with the enhanced coverage mode during the second subframe ofthe paging occasion comprises performing soft combining of the controlchannel associated with the enhanced coverage mode received in the firstsubframe of the paging occasion with the control channel associated withthe enhanced coverage mode received in the second subframe of the pagingoccasion.

According to some embodiments, the method further comprises: determiningthat there is no paging indication from the cellular base station forthe paging occasion if the signal strength of the control channelassociated with the enhanced coverage mode is above the signal strengththreshold after soft combining of the control channel associated withthe enhanced coverage mode received in the first subframe of the pagingoccasion with the control channel associated with the enhanced coveragemode received in the second subframe of the paging occasion; andattempting to decode the control channel associated with the enhancedcoverage mode during a third subframe of the paging occasion if thesignal strength of the control channel associated with the enhancedcoverage mode is below the signal strength threshold after softcombining of the control channel associated with the enhanced coveragemode received in the first subframe of the paging occasion with thecontrol channel associated with the enhanced coverage mode received inthe second subframe of the paging occasion.

According to some embodiments, the method further comprises, if a pagingindication is successfully decoded based on monitoring the controlchannel associated with the enhanced coverage mode: determining anamount of time to sleep until attempting to decode a paging messageindicated by the paging indication based at least in part on a number ofrepetitions of the control channel associated with the enhanced coveragemode occurred to successfully decode the paging indication and estimatedchannel conditions for the wireless device; entering a sleep mode forthe determined amount of time; and attempting to decode the pagingmessage indicated by the paging indication after the determined amountof time.

According to some embodiments, the wireless device remains in the sleepmode through at least one repetition of the paging message.

According to some embodiments, the wireless device comprises a dualsubscriber identity module dual standby (DSDS) device configured toconcurrently operate according to a first RAT and a second RAT in idlemode, wherein said monitoring the control channel associated with theenhanced coverage mode during the paging occasion is associated with thefirst RAT, wherein the method further comprises, determining that apaging occasion conflict exists between the first RAT and the secondRAT; and determining to skip monitoring one or more repetitions of thecontrol channel associated with the enhanced coverage mode for thepaging occasion to monitor a control channel associated with the secondRAT based at least in part on determining that the paging occasionconflict exists between the first RAT and the second RAT.

According to some embodiments, the method further comprises: providingan indication to the base station to serve the wireless device in theenhanced coverage mode based at least in part on the wireless devicecomprising a DSDS device.

According to some embodiments, the method further comprises: receiving abroadcast indication of a paging arrangement used by the cellular basestation, wherein monitoring the control channel associated with thenormal coverage mode during the paging occasion and monitoring thecontrol channel associated with the enhanced coverage mode during thepaging occasion if a paging indication is not successfully decoded onthe control channel associated with the normal coverage mode areperformed based at least in part on the broadcast indication of thepaging arrangement used by the cellular base station.

Another set of embodiments may include a method, comprising: by acellular base station: receiving an indication to page a wirelessdevice, attempting to page the wireless device using a first controlchannel; and attempting to page the wireless device using a secondcontrol channel if attempting to page the wireless device using thefirst control channel is unsuccessful.

According to some embodiments, the indication to page the wirelessdevice further indicates whether the wireless device is in a normalcoverage mode or an enhanced coverage mode, wherein the first controlchannel comprises a control channel associated with the normal coveragemode and the second control channel comprises a control channelassociated with the enhanced coverage mode when the wireless device isin the normal coverage mode, wherein the first control channel comprisesa control channel associated with the enhanced coverage mode and thesecond control channel comprises a control channel associated with thenormal coverage mode when the wireless device is in the enhancedcoverage mode.

Yet another set of embodiments may include a method, comprising: by acellular base station: receiving an indication to page a wirelessdevice, wherein the indication to page the wireless device furtherindicates whether the wireless device is in a normal coverage mode or anenhanced coverage mode and a number of previous attempts to page thewireless device that have occurred; determining whether to attempt topage the wireless device using a control channel associated with thenormal coverage mode or using a control channel associated with theenhanced coverage mode based at least in part on whether the wirelessdevice is in the normal coverage mode or the enhanced coverage mode andthe number of previous attempts to page the wireless device that haveoccurred; and attempting to page the wireless device using thedetermined control channel.

A further set of embodiments may include a method, comprising: by acellular base station: determining whether to page according to a firstpaging arrangement or a second paging arrangement; providing a broadcastindication of the determined paging arrangement; receiving an indicationto page a wireless device, and attempting to page the wireless deviceusing the determined paging arrangement.

According to some embodiments, the first paging arrangement comprisesalways paging using a control channel associated with an enhancedcoverage mode, wherein the second paging arrangement comprises initiallyattempting to perform paging using a control channel associated with anormal coverage mode and attempting to perform paging using the controlchannel associated with the enhanced coverage mode if attempting toperform paging using the control channel associated with the normalcoverage mode is unsuccessful.

According to some embodiments, determining whether to page according tothe first paging arrangement or the second paging arrangement is basedat least in part on current loading conditions for the cellular basestation.

According to some embodiments, the control channel associated with thenormal coverage mode comprises a third generation partnership project(3GPP) compliant physical downlink control channel (PDCCH); wherein thecontrol channel associated with the enhanced coverage mode comprises a3GPP compliant machine type communication (MTC) PDCCH (mPDCCH).

A still further exemplary set of embodiments may include an apparatus,comprising a processing element configured to cause a device toimplement any or all parts of the preceding examples.

Another exemplary set of embodiments may include a device, comprising:an antenna; a radio coupled to the antenna; and a processing elementoperably coupled to the radio, wherein the device is configured toimplement any or all parts of the preceding examples.

A yet further exemplary set of embodiments may include a non-transitorycomputer accessible memory medium comprising program instructions which,when executed at a device, cause the device to implement any or allparts of any of the preceding examples.

A still further exemplary set of embodiments may include a computerprogram comprising instructions for performing any or all parts of anyof the preceding examples.

Yet another exemplary set of embodiments may include an apparatuscomprising means for performing any or all of the elements of any of thepreceding examples.

In addition to the above-described exemplary embodiments, furtherembodiments of the present disclosure may be realized in any of variousforms. For example some embodiments may be realized as acomputer-implemented method, a computer-readable memory medium, or acomputer system. Other embodiments may be realized using one or morecustom-designed hardware devices such as ASICs. Still other embodimentsmay be realized using one or more programmable hardware elements such asFPGAs.

In some embodiments, a non-transitory computer-readable memory mediummay be configured so that it stores program instructions and/or data,where the program instructions, if executed by a computer system, causethe computer system to perform a method, e.g., any of a methodembodiments described herein, or, any combination of the methodembodiments described herein, or, any subset of any of the methodembodiments described herein, or, any combination of such subsets.

In some embodiments, a device (e.g., a UE 106 or 107) may be configuredto include a processor (or a set of processors) and a memory medium,where the memory medium stores program instructions, where the processoris configured to read and execute the program instructions from thememory medium, where the program instructions are executable toimplement any of the various method embodiments described herein (or,any combination of the method embodiments described herein, or, anysubset of any of the method embodiments described herein, or, anycombination of such subsets). The device may be realized in any ofvarious forms.

Although the embodiments above have been described in considerabledetail, numerous variations and modifications will become apparent tothose skilled in the art once the above disclosure is fully appreciated.It is intended that the following claims be interpreted to embrace allsuch variations and modifications.

What is claimed is:
 1. A method for operating a cellular base station,the method comprising: receiving an indication to page a wirelessdevice, wherein the indication to page the wireless device furtherindicates a number of previous attempts to page the wireless device thathave occurred; determining whether to attempt to page the wirelessdevice using a first control channel or using a second control channelbased at least in part on the number of previous attempts to page thewireless device that have occurred; and attempting to page the wirelessdevice using the determined control channel.
 2. The method of claim 1,the method further comprising: attempting to page the wireless deviceusing the first control channel for up to a first predetermined numberof attempts; and attempting to page the wireless device using the secondcontrol channel for up to a second predetermined number of attempts ifattempting to page the wireless device using the first control channelis unsuccessful for the first predetermined number of attempts.
 3. Themethod of claim 2, wherein the indication to page the wireless devicefurther indicates whether the wireless device is in a normal coveragemode or an enhanced coverage mode, wherein the first control channelcomprises a control channel associated with the normal coverage mode andthe second control channel comprises a control channel associated withthe enhanced coverage mode when the wireless device is in the normalcoverage mode, wherein the first control channel comprises a controlchannel associated with the enhanced coverage mode and the secondcontrol channel comprises a control channel associated with the normalcoverage mode when the wireless device is in the enhanced coverage mode.4. The method of claim 3, wherein the control channel associated withthe normal coverage mode comprises a third generation partnershipproject (3GPP) compliant physical downlink control channel (PDCCH);wherein the control channel associated with the enhanced coverage modecomprises a 3GPP compliant machine type communication (MTC) PDCCH(mPDCCH).
 5. The method of claim 1, the method further comprising:determining whether to page according to a first paging arrangement or asecond paging arrangement; and providing a broadcast indication of thedetermined paging arrangement, determining whether to attempt to pagethe wireless device using the first control channel or using the secondcontrol channel based at least in part on the number of previousattempts to page the wireless device that have occurred when pagingaccording to the second paging arrangement.
 6. The method of claim 5,the method further comprising, when paging according to the first pagingarrangement: always paging using a control channel associated with anenhanced coverage mode.
 7. The method of claim 1, wherein determiningwhether to page according to the first paging arrangement or the secondpaging arrangement is performed based at least in part on currentloading conditions for the cellular base station.
 8. An apparatus,comprising: a processing element configured to cause a cellular basestation to: receive an indication to page a wireless device, wherein theindication to page the wireless device further indicates a number ofprevious attempts to page the wireless device that have occurred;determine whether to attempt to page the wireless device using a firstcontrol channel or using a second control channel based at least in parton the number of previous attempts to page the wireless device that haveoccurred; and attempt to page the wireless device using the determinedcontrol channel.
 9. The apparatus of claim 8, wherein the processingelement is further configured to cause the cellular base station to:attempt to page the wireless device using the first control channel forup to a first predetermined number of attempts; and attempt to page thewireless device using a second control channel for up to a secondpredetermined number of attempts if attempting to page the wirelessdevice using the first control channel is unsuccessful for the firstpredetermined number of attempts.
 10. The apparatus of claim 9, whereinthe indication to page the wireless device further indicates whether thewireless device is in a normal coverage mode or an enhanced coveragemode, wherein the first control channel comprises a control channelassociated with the normal coverage mode and the second control channelcomprises a control channel associated with the enhanced coverage modewhen the wireless device is in the normal coverage mode, wherein thefirst control channel comprises a control channel associated with theenhanced coverage mode and the second control channel comprises acontrol channel associated with the normal coverage mode when thewireless device is in the enhanced coverage mode.
 11. The apparatus ofclaim 10, wherein the control channel associated with the normalcoverage mode comprises a third generation partnership project (3GPP)compliant physical downlink control channel (PDCCH); wherein the controlchannel associated with the enhanced coverage mode comprises a 3GPPcompliant machine type communication (MTC) PDCCH (mPDCCH).
 12. Theapparatus of claim 8, wherein the processing element is furtherconfigured to cause the cellular base station to: determine whether topage according to a first paging arrangement or a second pagingarrangement; and provide a broadcast indication of the determined pagingarrangement, wherein the processing element is configured to cause thecellular base station to determine whether to attempt to page thewireless device using the first control channel or using the secondcontrol channel based at least in part on the number of previousattempts to page the wireless device that have occurred when pagingaccording to the second paging arrangement.
 13. The apparatus of claim12, wherein the processing element is further configured to cause thecellular base station to, when paging according to the first pagingarrangement: always page using a control channel associated with anenhanced coverage mode.
 14. The apparatus of claim 12, whereindetermining whether to page according to the first paging arrangement orthe second paging arrangement is performed based at least in part oncurrent loading conditions for the cellular base station.
 15. A cellularbase station, comprising: an antenna; a radio coupled to the antenna;and a processing element coupled to the radio; wherein the cellular basestation is configured to: determine whether to page according to a firstpaging arrangement or a second paging arrangement; provide a broadcastindication of the determined paging arrangement; receive an indicationto page a wireless device, and attempt to page the wireless device usingthe determined paging arrangement.
 16. The cellular base station ofclaim 15, wherein to attempt to page the wireless device using the firstpaging arrangement, the cellular base station is further configured to:always page using a control channel associated with an enhanced coveragemode,
 17. The cellular base station of claim 15, wherein to attempt topage the wireless device using the second paging arrangement, thecellular base station is further configured to: initially attempt toperform paging using a control channel associated with a normal coveragemode; and attempt to perform paging using the control channel associatedwith an enhanced coverage mode if attempting to perform paging using thecontrol channel associated with the normal coverage mode isunsuccessful.
 18. The cellular base station of claim 17, wherein toattempt to page the wireless device using the second paging arrangement,the cellular base station is further configured to: determine whether toattempt to page the wireless device using the control channel associatedwith the normal coverage mode or using the control channel associatedwith the enhanced coverage mode based at least in part on a number ofprevious attempts to page the wireless device that have occurred; andattempt to page the wireless device using the determined controlchannel.
 19. The cellular base station of claim 17, wherein the controlchannel associated with the normal coverage mode comprises a thirdgeneration partnership project (3GPP) compliant physical downlinkcontrol channel (PDCCH); wherein the control channel associated with theenhanced coverage mode comprises a 3GPP compliant machine typecommunication (MTC) PDCCH (mPDCCH).
 20. The cellular base station ofclaim 15, wherein the cellular base station is further configured to:determine whether to page according to the first paging arrangement orthe second paging arrangement based at least in part on current loadingconditions for the cellular base station.